<!DOCTYPE html>
<html style="font-family: Ahem; font-size: 10px; -webkit-font-smoothing: none; color: white;">
<body>
<ruby id="ruby1">
A<i><div></div></i>B
</ruby>
<script>
    document.body.offsetTop;
    ruby1 = document.getElementById('ruby1');
    ruby1.insertBefore(document.createElement('rt'), ruby1.lastChild);
</script>
</body>
</html>

